/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package cn.icanci.snowstack.java8.chap3;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.net.URL;
import java.util.Enumeration;

public class ExecuteAround {

    public static void main(String[] args) throws IOException {

        // method we want to refactor to make more flexible
        String result = processFileLimited();
        System.out.println(result);

        System.out.println("---");

        String oneLine = processFile((BufferedReader b) -> b.readLine());
        System.out.println(oneLine);

        String twoLines = processFile((BufferedReader b) -> b.readLine() + b.readLine());
        System.out.println(twoLines);

    }

    private static String getPath() throws IOException {
        ClassLoader classLoader = ExecuteAround.class.getClassLoader();
        Enumeration<URL> resources = classLoader.getResources("lambdasinaction/chap3/data.txt");
        URL url = resources.nextElement();
        return url.getPath();
    }

    public static String processFileLimited() throws IOException {
        try (BufferedReader br = new BufferedReader(new FileReader(getPath()))) {
            return br.readLine();
        }
    }

    public static String processFile(BufferedReaderProcessor p) throws IOException {

        try (BufferedReader br = new BufferedReader(new FileReader(getPath()))) {
            return p.process(br);
        }

    }

    @FunctionalInterface
    public interface BufferedReaderProcessor {
        String process(BufferedReader b) throws IOException;
    }
}
